A call to a telephone user is sometimes forwarded to a service such as messaging service or assisting agent service. Such services are typically provided by a telephony service system external to the switch that serves the user's telephone line. Compared to a home answering machine, these service systems may be advantageous since they can provide more storage capacity and enable record tracking and post-call processing such as information redistribution.
Unlike the home answering machine, however, these service systems typically do not provide a way for the user to listen to the forwarded call while the interaction between the caller and the service system is in progress, e.g., while the caller is leaving a message with a messaging service system. Thus, the user cannot monitor and/or override the handling of the call like they would be able to do on a home answering machine. Yet, the user of the messaging service or assisting agent service often desires such monitoring and/or overriding of the service.
Some switch vendors provide a screening function from a serving switch which alerts the user about a call intercepted by a messaging or attendant system, and allows the user to screen the call. The cost of this switch function, however, is typically prohibitive. Another difficulty of the switch approach is that a switch operator cannot determine whether a call has been forwarded to a backup service system for which screening options are desired, or to another destination where such options are not desired. Moreover, most switches today do not include a call screening function and the call screening function is not available to users and/or call backup service providers served by such switches.
Thus, there is a need for an improved call monitoring and overriding system and method to handle the calls forwarded to a service system.